Production
General Properties of Fused Quartz Glass
Fused quartz glass is practically single component glass consisting of SiO2. Silicon dioxide is in amorphous form and the temperature drop does not crack it, like f.g. crystalline quartz.
Fused quartz glass has a unique combination of physical and chemical properties: high optical homogeneity, small light absorption ( usual window glass absorbs the same quantity of light as quartz glass with the thickness of 100 m), resistance to the ionizing radiation and high intensity laser radiation, low coefficient of temperature expansion. All fused quartz glass products are thermally and chemically inert, the action of organic and inorganic acids except for hydrofluoric and phosphoric acid (heat to more than 300°C) do not affect them.
Almost all analytical solutions and precipitates are interacted chemically with fused quartz glass that is why platinum chemical ware can be successfully replaced by fused quartz glass chemical ware. Fused quartz glass products can be subjected under high temperature and pressure conditions (operating temperature 1250°C),dynamic and vibrating loads, kinetic heating and shock cooling, nucleus space radiation.
Fused quartz glass products are widely used in the following industries: atomic power, chemical machine manufacture, radio electronics, aircraft and space machinery, metallurgy, lighting, precision instrument making and many others.
- Thermal properties:
- 1.1 Coefficient of linear expansion α average for interval 293-1273 K.
temperature, К (оС) α*107, К-1 temperature, К (оС) α*107, К-1 temperature, К (оС) α*107, К-1 213 (-60) 2.0 573 (300) 5.9 873 (600) 5.6 323 (50) 4.0 623 (350) 5.8 923 (650) 5.5 373 (100) 5.0 673 (400) 5.8 973 (700) 5.4 423 (150) 5.5 723 (450) 5.8 1023 (750) 5.3 473 (200) 5.6 773 (500) 5.7 1073 (800) 5.2 523 (250) 5.7 823 (550) 5.7 - 1.2 Annealing point
Glass type Annealing temperature, К (оС) lower (corresponds to viscosity 1013,5 Pa·s) upper (corresponds to viscosity 1012 Pa·s) КВ 1363 (1090) 1453 (1180) КУ-2 1343 (1070) 1443 (1170) - 1.3 Temperature of deformation (corresponds to viscosity 1010Pa·s)
quartz glass type deformation point, К (оС) KV 1613 (1340) KU-2 1603 (1330) - 1.4 Soft point (corresponds to viscosity 106,6 Па·с)
quartz glass type soft temperature, К (оС) KV 1973 (1700) KU-2 1993 (1720)
- 1.1 Coefficient of linear expansion α average for interval 293-1273 K.
- Electric properties
- 2.1 Electric resistance
- at 293 К (20оС) — higher 1·1020 Ом·м;
- at 773 К (500оС)- 7·109 Ом·м;
- 2.2 Dielectric constant e at frequency of 9,5·109 Hz
- at 293 К (20оС) — 3,8;
- at 1273 К (1000оС) — 4,0;
- 2.3 Dielectric strength;
- at 293 К (20оС) — more than 3,5·104 кВ/м;
- 2.1 Electric resistance
- Mechanical properties
- 3.1 Bending strength s, MPa:
- at 293 К (20оС) — not less than 39,2;
- at 1073 К (1000оС) — not less than 68,7;
- 3.2 Ultimate strength s, MPa:
- at compression — 588,6;
- at shock bending — 0,196-0,294;
- 3.3 Young’s modulus
- Е — 73,6 GPa.
- 3.4 Density
- at 293 К (20оС)-2,21·103 kg/m3
- 3.5 Bruster’s coefficient
- in visible spectrum part — (3,5-3,7)-12 m2/N
- 3.1 Bending strength s, MPa: